1. Field of the Invention
The invention relates to a molding machine, for molding products, such as containers.
2. Description of the Related Art
As shown in FIG. 1, a conventional blow molding machine 1 includes opposite first and second molds 12, 13 disposed to a base (not shown), and a push unit 14 disposed to the base for pushing the second mold 13 against the first mold 12. The push unit 14 includes a hydraulic motor 141 disposed to said base, a support 142 disposed to the base and spaced apart from the hydraulic motor 141, and a linkage mechanism 143 having levers 144 connected pivotally and respectively to the second mold 13, the hydraulic motor 141, and the support 142. When using the conventional molding machine 1, the hydraulic motor 141 drives the linkage mechanism 143, thereby pushing the second mold 13 to move toward and eventually to couple with the first mold 12.
However, since each of the levers 144 of the linkage mechanism 143 has a fixed length, the displacement of the second mold 13 is fixed. Wear and deformation of the levers 144 may change the displacement of the second mold 13 and reduce the coupling strength between the first and second molds 12, 13, thereby affecting the quality of the container products. In addition, the coupling strength between the first and second molds 12, 13 may decrease due to an oil leakage of the hydraulic motor 141 of the push unit 14.